If it can't be cancelled, it can't be refunded. If you can't get a tax refund, you have to sell it domestically. If you switch to domestic sales, you have to pay taxes. Solution: Write-off does not necessarily depend on the goods bought by the guest, but on the remittance memo of that guest. Payment documents of other bills can be written off temporarily, and other bills can be written off after foreign exchange is remitted, according to the principle of writing off first. The water fee will not expire.